Hypodermic needle



Aug. 21, 1923. 1,465,851

7 O. W. KRESS Y HYPODERMIC NEEDLE Filed Jan. 2, 1923 avwem co'o -,ean

Patented Aug. El, 1323.

I, 1,4t5,851 Ars'r re n.

.osoAnw. KRESS, or warnnnoo, rown.

. HYPODERMIC NEEDLE.

Application filed January 2, 1923. Serial 11o. 610,286 1 thisapplication is a hypodermic needle, and,

in order that the objects of the invention may be understood clearly,and to the end that the specific problem to be solved may be presentedproperly, it is necessary to comment at some length, but withoutderogation, upon the prior art.

It is a matter of common knowledge that a hypodermic needle often breaksor bends when in use, and, if bent, is straightened, a complete ruptureoccurring subsequently at the point of bending and straightening, and aportion of the needle remaining embedded in the tissue. To remedy thiscondition, it has been proposed hitherto to mount upon the needle aguard which is adjustable longitudinally of the needle, the needle beingof a common diameter and of a uniform strength between the guard and thepoint of the needle, and the needle being reduced in diameter'andweakened. to the rear of the guard, upon the supposition that if the needle bends or breaks at all, it will do so at the point where itisweakened, the guard remaining exposed. so that the portion of the needlewhich is broken off may be readily withdrawn from the tissue wherein itis embedded.

Two. diilicultie's present themselves, in the manipulation of a needleof the sort last above described. First, the operator, seeking a deeppoint of application, often shifts the adjustable guard until theweakened place, lies between the guard and the point of the needle, theresult being that the needle breaks between the point and the guard, thesevered part remaining inaccessibly embedded in the flesh. It ispossible, to obtain from the prior art, the suggestion that the guard befixed, but this does not afford an adequate remedy, in view of a seconddifli culty which will now be explained.

Even though the guard be fixed and the needle weakened to the rear ofthe guard, the needle sometimes will break between the point of theneedle and the guard, if the needle is of uniform cross section andneedle, That portion of the needle which is immediately in front of theguard may be embedded in tough muscle tissue which reinforces the needlein front of the guard and closely adjacentthereto, the point portion.

of the needle being in relatively soft tissue, affording noreinforcement, and'wherein a bone or other deflecting obstructionexists. Then, notwithstanding the weakening of the needle to the rear ofthe guard, the point may break ofi'.

The undesirable features above enumerated are obviated in a hypodermicneedle provided intermediate its ends With a fixed outstanding guard,and comprising'a body which is increased in diametergradually plied suchahypodermic needle, and it is the object ofthis invention to provideone.

It is withinthe province of the disclosure to improve generally and toenhance the' from its entering end to the guard, the neeutility ofdevices of that type to which the invention appertains.

With the above and other objects in View, which will appear as the.description pro ceeds, the invention resides-inthe combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understoodthat, with- V in the scope ofwhat is claimed, changes in the precise embodiment of the inventionshown can be made without departing from the spirit of the invention.

In the drawings '1 Figure 1 shows in elevation and on a greatly enlargedscale, a hypodermic needle constructed in accordance with the invention;and Figures 2 and 3 and 4 are sections The needle forming the subjectmatter of I whichis increased gradually in diameter, as

shown at 4, from its beveled entering end 5 to the guard 2,the needlecomprisingaweakened portion 6, of uniform diameter from end to end, theweakened portion 6 connecting the body 4 with the hub 7 of the needle,

said portion 6 being of less diameterthan the body and the hub, andbeing located to the rear of the fixed guard 2; The tapered form of thebody 3 reduces the pain incident to the initial introduction of. theneedle, and the general construction accomplishes the objects of theinvention as hereinbefore; set

forth.

hat is claimed is A hypodermic needle provided intermediate its endswith a fixed outstanding guard and comprising a body Whichi's increasedin diameter gradually from its ent-eri-ng -end to the guard, theneedlecomprising-a weakened portion/located to the rear of the guard and ofless diameter than the body.

' In testimony that I claim the foregoing as my own, I have heretoaflixed my signal ture in the presence of two witnesses.

V "OSCAR W. KRESS. Witnesses: V

E. R. MCCOY, FERN F. DEAN.

